CA2200729C - Lan tester - Google Patents
Lan tester Download PDFInfo
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- CA2200729C CA2200729C CA002200729A CA2200729A CA2200729C CA 2200729 C CA2200729 C CA 2200729C CA 002200729 A CA002200729 A CA 002200729A CA 2200729 A CA2200729 A CA 2200729A CA 2200729 C CA2200729 C CA 2200729C
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L43/00—Arrangements for monitoring or testing data switching networks
- H04L43/50—Testing arrangements
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- Computer Networks & Wireless Communication (AREA)
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- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
- Small-Scale Networks (AREA)
- Monitoring And Testing Of Transmission In General (AREA)
Abstract
A LAN tester for carrying out a conduction test, a polarity test and an operation test of LAN wiring includes a power supply section for supplying a power supply current to one of paired signal lines to be tested at one end thereof; a current detecting section for detecting the current flowing through the other of the signal lines; a forward polarity detecting section for detecting positive and negative pulses from positive and negative signal lines, respectively; a reverse polarity detecting section for detecting negative and positive pulses; a first change-over switch for operating the power supply section and the current detecting section in a conduction test mode and operating the forward polarity detecting section and the reverse polarity detecting section in a polarity test mode; and a second change-over switch for realizing an operation test mode by connecting a connection terminal of a transmission signal line and a connection terminal of a reception signal line for looping in the polarity test mode. According to this arrangement, the LAN tester can be provided which is capable of carrying out a cable conduction test and a reverse connection confirmation test as well as a simple operation test with a hub included, only at one end.
Description
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Description LAN TESTER
Technical Field The present invention relates to a testing device which can easily perform disconnection, short circuit and polarity checks, a connection test, a reverse connection test and the like in a LAN (Local Area Network).
Background Art Conventionally, relatively small-scale data processing devices, such as personal computers, have been normally used independently.
However, owing to the recent improvement in data throughput and the recent tendency in down-sizing, construction of a distributed processing system by connecting a plurality of data processing devices within a specific area in a company or a department to form a network or construction of a simple network rather than performing a distributed processing, for example, has been frequently performed for effectively using accumulated data.
Such a network is generally called a LAN. The simplest LAN
construction includes an arrangement wherein a network OS
(Operating System) and peer-to-peer IOBASE2 or lOBASE-T, etc. are combined. Among them, the LAN connection based on lOBASE-T is relatively simple and can be carried out at a user side without asking an expert. For this reason, upon constructing the LAN based on lOBASE-T, the wiring thereof has been often done by the user individually.
However, even though the lOBASE-T wiring is so easy, if there is a wiring miss, the network does not work. Further, as a scale of the LAN increases, the number of cables also increases so that the wiring thereof becomes complicated. Under these circumstances, if, for example, a fault, such as cable disconnection or miswiring, occurs, a S procedure is necessary for finding which cable is subjected to the fault.
For such a procedure, a method has been used, wherein loopback connectors are connected to both ends of each cable and a dedicated cable tester including a loop resistance, etc. is connected, and then a conduction test is carried out relative to each cable, so that presence/absence of disconnection or miswiring can be confirmed per cable to search for a cable which is subjected to the fault.
However, in such a conventional disconnected cable searching method, it is necessary to connect the loopback connectors to both ends of a cable to be tested. In order to connect, after connecting a loopback connector to one end, a loop back connector also to the other end, an operation is necessary for tracing the cable having the loopback connector connected to one end thereof. This operation for $nding out the cable to which the loopback connector is connected is an awful operation in the complicated wiring. Thus, the conventional conduction test requires extremely large labor for finding the fault.
Further, a problem is raised, wherein the connecting operation for the loopback connector for performing the conduction test causes a new fault, such as misconnection or contact failure, etc. Moreover, the conventional conduction test has a problem that only a test for cable can be achieved, and a connection confirmation test inclusive of a hub, etc. can not be achieved.
Description LAN TESTER
Technical Field The present invention relates to a testing device which can easily perform disconnection, short circuit and polarity checks, a connection test, a reverse connection test and the like in a LAN (Local Area Network).
Background Art Conventionally, relatively small-scale data processing devices, such as personal computers, have been normally used independently.
However, owing to the recent improvement in data throughput and the recent tendency in down-sizing, construction of a distributed processing system by connecting a plurality of data processing devices within a specific area in a company or a department to form a network or construction of a simple network rather than performing a distributed processing, for example, has been frequently performed for effectively using accumulated data.
Such a network is generally called a LAN. The simplest LAN
construction includes an arrangement wherein a network OS
(Operating System) and peer-to-peer IOBASE2 or lOBASE-T, etc. are combined. Among them, the LAN connection based on lOBASE-T is relatively simple and can be carried out at a user side without asking an expert. For this reason, upon constructing the LAN based on lOBASE-T, the wiring thereof has been often done by the user individually.
However, even though the lOBASE-T wiring is so easy, if there is a wiring miss, the network does not work. Further, as a scale of the LAN increases, the number of cables also increases so that the wiring thereof becomes complicated. Under these circumstances, if, for example, a fault, such as cable disconnection or miswiring, occurs, a S procedure is necessary for finding which cable is subjected to the fault.
For such a procedure, a method has been used, wherein loopback connectors are connected to both ends of each cable and a dedicated cable tester including a loop resistance, etc. is connected, and then a conduction test is carried out relative to each cable, so that presence/absence of disconnection or miswiring can be confirmed per cable to search for a cable which is subjected to the fault.
However, in such a conventional disconnected cable searching method, it is necessary to connect the loopback connectors to both ends of a cable to be tested. In order to connect, after connecting a loopback connector to one end, a loop back connector also to the other end, an operation is necessary for tracing the cable having the loopback connector connected to one end thereof. This operation for $nding out the cable to which the loopback connector is connected is an awful operation in the complicated wiring. Thus, the conventional conduction test requires extremely large labor for finding the fault.
Further, a problem is raised, wherein the connecting operation for the loopback connector for performing the conduction test causes a new fault, such as misconnection or contact failure, etc. Moreover, the conventional conduction test has a problem that only a test for cable can be achieved, and a connection confirmation test inclusive of a hub, etc. can not be achieved.
The present invention has a subject to solve the foregoing problems and to provide a LAN tester which is capable of carrying out a cable conduction test and a miswiring confirmation test as well as a simple operation test inclusive of a hub, etc. only at one end.
S Disclosure of Invention For achieving the foregoing subject, when performing a conduction test, a LAN tester of the present invention selects (or non-optional) a conduction test mode as an operation mode by a change-over switch (first change-over switch), and comprises a power supply section for supplying, at one end of paired signal lines having two signal lines, a power supply current to one of the signal lines, and a current detecting section for detecting, at the one end of the paired signal lines to be tested, the current flowing in the signal line to which no power supply current is supplied by the power supply section. By this arrangement, when a fault, such as disconnection, exists in the signal line, the current is not detected by the current detecting section, while, when no abnormality exists in the signal line, a given current is detected by the current detecting section.
When performing a polarity test, a LAN tester of the present invention selects (or non-optional) a polarity test mode as an operation mode by a change-over switch (first change-over switch), and comprises a forward polarity detecting section for detecting positive pulses from a posifilve signal line and negative pulses from a negative signal line at one end of the signal lines to be tested, and a reverse polarity detecting section for detecting negative pulses from the positive signal line and positive pulses from the negative signal _~ __ . _ _ ~ ~ _ ~ . r.~.~_ ___ __ ._ line at the one end of the signal lines to be tested. By this arrangement, when the pulses are detected by the forward polarity detecting section, it is confirmed that the signal lines are in the normal polarity. On the other hand, when the pulses are detected by the reverse polarity detecting section, it is confirmed that the signal lines are in the reverse polarity.
When performing an operation test, a L.AN tester of the present invention selects (or non-optional) an operation test mode as an operation mode by a first change-over switch and a second change-over switch, and comprises a loopback connecting section for connecting terminals for connecting transmission signal lines and terminals for connecting reception signal lines, respectively.
a forward polarity detecting section for detecting positive pulses from a positive signal line and negative pulses from a negative signal line at one end of the signal lines to be tested, and a reverse polarity detecting section for detecting negative pulses from the positive signal line and positive pulses from the negative signal line at the one end of the signal lines to be tested. By this arrangement, since the pulses in the transmission signal lines are looped back to the reception signal lines so as to produce a false signal, an operation state of the hub or AUI (Attachment Unit Interface) (terminal) to be connected can be confirmed by the forward polarity detecting section and the reverse polarity detecting section.
When performing a confirmation test of a connecting direction, a LAN tester of the present invention, similar to the case of the conduction test, selects (or non-optional) a conduction test mode as an operation mode by a change-over switch (first change-over switch), t and comprises a power supply section for supplying a power supply current to one of signal lines at one end of the paired signal lines to be tested, a current detecting section for detecting, at the one end of the paired signal lines, the current flowing in the signal line to ~~hich no S power supply current is supplied by the power supply section, and a reverse connection confirmation circuit connected to the two signal lines at the other end of the paired signal lines. The reverse connection confirmation circuit includes a pair of unidirectional elements connected reversely in parallel, at least one of which unidirectional elements indicates a state thereof upon energization.
By this arrangement, since the states of the unidirectional elements in the reverse connection confirmation circuit differ depending on the forward connection and the reverse connection, the connection state can be confirmed.
For performing a confirmation test of connecting directions about a plurality of the paired signal lines, it is preferable to arrange a plurality of the reverse connection confirmation circuits, and provide power supply control means for controlling a power feed timing of the power supply section supplying a power supply current to the plurality of paired signal lines connected to the respective reverse connection confirmation circuits.
Brief Description of Drawings Fig. 1 is a circuit diagram showing an embodiment of a LAN
tester according to the present invention. Fig. 2 is a diagram showing a connection relationship to a hub or AUI when performing a conduction test using the LAN tester of the present invention. Fig. 3 is a diagram extracting the principal part of Fig. 1 for explaining an operation example in the conduction test using the LAN tester of the present invention. Fig. 4 is a diagram showing a connection relationship to a hub when performing a polarity test using the LAN
tester of the present invention. Fig. 5 is a diagram showing a connection relationship to a hub and an AUI when performing communication monitoring using the LAN tester of the present invention. Fig. 6 is a diagram extracting the principal part of Fig. 1 for explaining an operation example in the polarity test and the communication monitoring using the LAN tester of the present invention. Fig. 7 is a diagram showing a waveform example of trigger pulses (carrier component) in Fig. 4. Fig. 8 is a diagram showing a waveform example during communication in Fig. 5. Fig. 9 is a diagram showing a connection relationship to a hub or AUI when performing a simple operation test using the LAN tester of the present invention. Fig. 10 (a) and (b) are diagrams extracting the principal part of Fig. 1 for explaining an operation example in the simple operation test using the LAN tester of the present invention. Fig. 11 is a diagram showing a structural example wherein a confirmation test of presence/absence of miswiring of a universal 8-pin modular jack to be used in the LAN wiring is performed. Fig. 12(a) is a diagram showing a state wherein paired signal lines are connected in the forward direction. Fig. 12(b) is a diagram showing a state wherein the paired signal lines are reversely connected. Fig. 13 (a) and (b) are diagrams both showing states wherein misconnection exists between different paired signal lines.
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_,_ Best Mode for Carrying Out the Invention Now, an embodiment of a LAN tester of the present invention will be described with reference to Figs. 1-10.
Fig. 1 is a circuit diagram showing an example when carrying out the LAN tester. The LAN tester roughly includes a power supply section 2, a current detecting section 3, a forward polarity detecting section 4, a reverse polarity detecting section 5, a first change-over switch (change-over switch) 6, and a second change-over switch 7 having a function of a loopback connecting portion. In the figure, RA
and RB denote reception terminals, and SA and SB denote transmission terminals.
The power supply section 2 includes a power supply switch SWP
and an internal battery E. The current detecting section 3 includes a bipolar transistor ~3, light-emitting diodes LYl and LY2 which light up in yellow, and a plurality of resistors R 1, R7, R8 and R 14. The resistors R7 and R8 are provided for turning on the bipolar transistor ~3 while turning off a bipolar transistor (~2 so as to supply the power supply current to the transmission terminal SA. It is suitable to set R 1 and R 14 to about 56052, respectively, and R7 and R8 to about l OkS2.
The forward polarity detecting section 4 includes a bipolar transistor g4, a field-effect transistor ~5, a light-emitting diode LG
which lights up in green, resistors R12, R13, R15 and R16, and a capacitor C2. The reverse polarity detecting section 5 includes the bipolar transistor ~2, a field-effect transistor gl, a light-emitting diode LR which lights up in red, resistors R4, R5, R6 and R9, and a _ g_ capacitor C 1. The resistors R 10 and R 11 are provided for applying biases to the bipolar transistors ~2 and ~4. The capacitor C 1 and the resistor R5, and the capacitor C2 and the resistor R15 constitute smoothing circuits, respectively. It is suitable to set R6, R9, R 12 and S R 13 to about 1 kS2, respectively, R 10 to about 27052, R 11 to about 4.7kS2, R4 and R 16 to about 500kS2, respectively, R5 and R 15 to about 5MS2, respectively, and C 1 and C2 to about 0.1 ~,F, respectively.
As shown in Fig. 3, the first change-over switch 6 performs an on-off operation for a connection terminal 1 a and includes a switch SW 1 for connecting the transmission terminal SB to a connection terminal 2a or 2b. As shown in Fig. 10(b), the second change-over switch 7 includes a switch SW2 for connecting between the transmission terminal SA and the reception terminal RA and between the transmission terminal SB and the reception terminal RB.
Now, tests using the LAN tester of the present invention will be explained, respectively.
Fig. 2 is a diagram showing a connection relationship to a hub (or AUI) 20 when performing a conduction test using the LAN tester of the present invention. Fig. 3 is a circuit diagram extracting the principal part of Fig. 1 for explaining an operation example in the conduction test.
Specifically, in the conduction test, the bipolar transistor ~2 is turned off when the bipolar transistor ~3 is turned on, and monitoring of pilot data is stopped. Further, by opening the switch SW 1 (porrion 2b), a signal current does not flow to the bipolar transistor ~4 which thus does not operate. Accordingly, the LAN
_._ . __~~~~- . _.._ _~___ ._~ _ tester 1 shown in Fig. 1 becomes equivalent to a circuit shown in Fig.
3.
First, when performing a conduction test of reception lines, as shown in Fig. 2, the hub 20 is connected to the reception terminals S RA and RB of the LAN tester l, and the power supply switch SWP is closed. In this state, when the switch SW1 is pushed, the power supply current flows through the reception terminals RA and RB and then along a path of light-emitting diode LY1--thode D1-resistor Rl~switch SW1 (portion la)-ground GND as shown in Fig. 3, provided that the reception lines or the hub 20 is normal. Thus, the light-emitting diode LY1 lights up in yellow to notify to the external that the reception lines are normal.
On the other hand, if there is a fault, such as disconnection, in the reception line or the hub 20, the foregoing current path is interrupted. Thus, the light-emitting diode LY1 does not light up so that an occurrence of abnormality in the reception line or the hub 20 is recognized.
On the other hand, when performing a conduction test of transmission lines, as shown in Fig. 2, the hub 20 is connected to the transmission terminals SA and SB of the LAN tester 1, and the power supply switch SWP is closed. In this state, when the switch SW1 is pushed, the base current of the bipolar transistor ~3 flows to the ground GND through the resistor R8 and the switch SW1 (portion la) so that the bipolar transistor ~3 is turned on.
When the bipolar transistor ~3 is turned on, the power supply current flows through the transmission terminals SA and SB and -~~~..r. T.. r..~,."r,_~_~._ along a path of switch SW 1 (portion 2a)-resistor R 14-->light-emitting diode LY2-ground GND as shown in Fig. 3, provided that the transmission lines or the hub 20 is normal. Thus, the light-emitting diode LY2 lights up in yellow to notify to the external that the S transmission lines or the hub 20 is normal.
On the other hand, if there is a fault, such as disconnection, in the transmission line or the hub 20, the foregoing current path is interrupted. Thus, the light-emitting diode LY2 does not light up so that an occurrence of abnormality in the transmission line or the hub 20 is recognized.
As described above, the conduction test of the distribution cable is carried out through coils in the hub or AUI without using a loopback tool. Specifically, since no loopback tool is used, the conventional distribution cable tracing operation becomes unnecessary so that the labor for the searching operation can be largely reduced.
Fig. 4 is a diagram showing a connection relationship to a hub 40 when performing a polarity test using the LAN tester 1 of the present invention. Fig. 5 is a diagram showing a connection relationship to the hub 40 and an AUI 50 when performing communication monitoring using the LAN tester 1 of the present invention. Fig. 6 is a circuit diagram extracting the principal part of Fig. 1 for explaining an operation example in the polarity test and the communication monitoring.
Specifically, in the polarity test and the communication monitoring, since the bipolar transistor ~3 is turned off, the bipolar transistors ~2 and ~4 are activated. By connecting the switch SW1 ______...__ __~__.__.....
' 11-(portion 2b) to the terminal SB, the monitoring function of the pilot data is effected. Accordingly, the LAN tester 1 shown in Fig. 1 becomes equivalent to a circuit shown in Fig. 6.
As shown in Fig. 4, when performing a polarity test of the hub S 40, the hub is connected to the terminals SA and SB of the LAN
tester l, and the power supply switch SWP is closed. In this state, since the switch SW1 is not pushed, the base current does not flow to the bipolar transistor ~3. Thus, the bipolar transistor ~3 is turned off, and a certain bias is applied to the bipolar transistor ~2 and the bipolar transistor ~4 based on a voltage dividing ratio of the power supply voltage set by the resistors R 10 and R 11.
In this state, if a pulse signal as shown in Fig. 7 is applied as trigger pulses such that positive pulses are successively applied to the terminal SA and negative pulses are successively applied to the terminal SB, the base current intermittently flows to the bipolar transistor ~4 corresponding to the application of pulses. Thus, the bipolar transistor f~4 is intermittently turned on.
When the bipolar transistor ~4 is intermittently turned on, intermittent pulse voltages are applied to the field-effect transistor ~5 via the resistor R16. However, since the pulse voltages are smoothed by a time constant circuit constituted by the resistor R 15 and the capacitor C2, the field-effect transistor ~5 is turned on so that the light-emitting diode LG lights up in green to notify to the external that connection is performed with the correct polarity (forward polarity).
On the other hand, if negative pulses are successively applied to the terminal SA and positive pulses are successively applied to the T~,~_____ .~ J_~.. _r.~. _______ terminal SB, the base current intermittently flows to the bipolar transistor ~2 corresponding to the application of pulses. Thus, the bipolar transistor ~2 is intermittently turned on.
When the bipolar transistor ~2 intermittently is turned on, intermittent pulse voltages are applied to the field-effect transistor ~ 1 via the resistor R4. However, since the pulse voltages are smoothed by a time constant circuit constituted by the resistor R5 and the capacitor C 1, the field-effect transistor ~ 1 is turned on so that the light-emitting diode LR lights up in red to notify to the external that connection is performed with the wrong polarity (reverse polarity).
As described above, through the lighting-up of the light-emitting diode LG or the light-emitting diode LR, confirmation of presence/absence of the signal and confirmation of the polarity can be easily performed.
On the other hand, when performing the communication monitoring, the LAN tester 1 of the present invention is inserted between communication cables and, as shown in Fig. 5, the hub 40 and the AUI 50 are connected thereto. Accordingly, when a communication waveform as shown in Fig. 8 is applied, the communication state can be monitored through the foregoing operation in the polarity test.
Speci$cally, when a waveform is applied such that positive pulses are successively applied to the terminal SA and negative pulses are successively applied to the terminal SB, the light-emitting diode 2 S LG lights up in green. On the other hand, when a waveform is applied such that negative pulses are successively applied to the terminal SA
~~ i_i..~ _ __ _~.._~ J n---T-.-~-~ ___._ _ __ _ __.
and positive pulses are successively applied to the terminal SB, the light-emitting diode LR lights up in red. Accordingly, through the lighting-up of the light-emitting diode LG or LR, the signal can be easily monitored. As shown in Fig. 7, the signal voltages fed through S the cable for activating the transistor ~ 1 or ~5 are in the form of very short pulses. Thus, even if the light-emitting diode LG or LR is activated to light up based on these pulses, it is difficult to recognize it with the naked eye. In view of this, a width of a lighting time is ensured using the capacitor C 1 or C2 so as to make it easy to watch the lighting state.
As described above, the judgment of the polarity can be easily performed by detecting directions of the signal pulses, that is, based on the on-off states of the two light-emitting diodes LG and LR.
Fig. 9 is a diagram showing a connection relationship to the hub 40 when performing a simple operation test using the LAN tester 1 of the present invention. Fig. 10 is a diagram extracting the principal part of Fig. 1 for explaining an operation example in the simple operation test using the LAN tester of the present invention.
Specifically, in the simple operation test of the hub 40, since the bipolar transistor t~3 is turned off, the bipolar transistors ~2 and ~4 are activated. Further, since the pilot data monitoring function is activated by connecting the switch SW 1 (portion 2b) to the terminal SB, the LAN tester 1 shown in Fig. 1 becomes equivalent to a circuit shown in Fig. 10(a). As shown in Fig. 10(b), connections between the terminal RA and the terminal SA and between the terminal RB and the terminal SB are established for looping by closing the switch SW2.
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As shown in Fig. 9, when performing the simple operation test of the hub 40, the terminals SA and SB of the LAN tester are connected to the terminals RA and RB, respectively, and the power supply switch SWP is closed. Through this, pulses in the transmission lines are sent S to the reception lines so as to produce a false signal.
Specifically, as shown in Fig. 9, when the LAN tester 1 of the present invention is connected to the hub, the hub outputs again a signal voltage, as response data, into the transmission lines based on a looped-back signal. Accordingly, similar to the foregoing operation example in the communication monitoring, the simple operation test can be performed based on confirmation of PART/LINK of the hub 40 and irregular lighting-up/off of the light-emitting diodes LG and LR.
When the LAN tester 1 of the present invention is connected to the AUI, a simple operation test can be performed, similar to the case of the hub 40, based on lighting of R/L lamps of the AUI and irregular lighting-up/off of the light-emitting diodes LG and LR.
Specifically, the test of connection to the apparatus or the simple operation test can be accomplished simply by looping the signal lines.
As described above, by detecting the signal in the wiring to discriminate the presence / absence and the polarity thereof and performing the false operation test through the display using the light-emitting diodes and the looping by means of the LAN tester, the simple operation test of the hub or AUI and the confirmation of connection between the apparatuses can be achieved. Therefore, the disconnection, short circuit and polarity checks of a twisted-pair cable __._ . __._m.~~. ___T _.~~_ __ ,~~_ ..._ ._ of lOBASE-T as well as the simple connection test of the hub or AUI
can be achieved. Through this, if the LAN communication can not be achieved with the AUI, the test can be easily carried out to see whether the connections between the hub and the cable and between the cable and the AUI are securely performed. Thus, operation failure or contact failure of the hub, disconnection or short circuit of the cable, operation failure of the AUI or the like can be checked.
Further, in the conduction test, since the loopback tool, such as the loopback connector, is not used, it is not necessary to trace the distribution cable so that the searching operation is largely reduced, and further the test can be performed with one end of the cable connected to the apparatus. Thus, the confirmation of polarity and the operation test of the hub or AUI can be easily carried out.
In the foregoing embodiments, when performing the conduction test with the hub or AUI included, the hub or AUI is limited to such a type having a pulse transformer which forms a do loop in the HUB or AUI. On the other hand, no limiting conditions are given to the polarity test, the simple operation test, the communication monitoring and the like including the conduction test of the cable only.
Now, explanation will be given to a case wherein a confirmation test of a connecting direction of the wiring .is performed using the LAN
tester of the present invention. Fig. 11 is a diagram showing a structural example wherein, for example, a confirmation test of presence/absence of miswiring of a universal 8-pin modular jack to be used in the LAN wiring is performed. As shown in Fig. 11, the LAN
tester is provided with, for example, a plurality of reverse connection 2~ ~0 72~
confirmation circuits 12a, 12b ~ ~ ~ to be connected to corresponding reception terminals of the modular jack. Each of the reverse connection confirmation circuits 12a and 12b includes a diode D 11 (D 12) and a light-emitting diode LD 1a (LD2a) which are in reverse S connection.
One-side ends of paired signal lines 1 la and 1 lb are connected to pins 1 and 2 of a modular hack (MJ) 10 to be tested, respectively. To one of the paired signal lines, for example, to the signal line 11 a connected to the pin 1 of the MJ 10, is supplied the current from the forgoing power supply section 2 based on the do voltage Ea. further, between the signal line 11 b connected to the pin 2 of the MJ 10 and a grounding line is connected a light-emitting diode LD 1 b which lights up upon energization. The other-side ends of the signal lines 11 a and 11 b are connected to the foregoing reverse connection confirmation circuit 12a.
As shown in the figure, paired signal lines 11 c and 11 d are further connected to pins 3 and 6 of the MJ 10. Accordingly, similar to the case of the foregoing paired signal lines 11 a and 11 b, the current based on the do voltage Eb is supplied to the pin 3, a light-emitting diode LD2b is connected between the pin 6 and a grounding line, and a reverse connection confirmation circuit 12b is connected to the other-side ends of the paired signal lines 11 c and 11 d.
Upon performing the test, the currents based on the do voltages Ea and Eb are fed from the power supply section 2 at different timings, respectively. Since the known technique can be employed for switching itself of the power feed timing, it is not shown in the figure.
~~ p0 729 For the light-emitting diodes LD 1 b and LD2b, the circuits of the foregoing current detecting section 3 can be used as they are.
Now, a concrete example of the confirmation test of the connecting direction using the LAN tester with the foregoing structure will be described with reference to Figs. 12 and 13.
Fig. 12(a) is a diagram showing a state wherein the wiring of the MJ 10 is normal, that is, the paired signal lines 11 a and 11 b are connected in the forward direction. In this case, the current supplied through the pin 1 of the MJ 10 flows through the diode D 11 of the reverse connection confirmation circuit 12a to reach the pin 2 of the MJ 10 so that the light-emitting diode LDla lights up. Through this, it can be visually confirmed that the wiring of the MJ 10 is normal.
Fig. 12(b) is a diagram showing a state wherein the wiring of the MJ 10 is abnormal, that is, the paired signal lines 11 a and 11 b are reversely connected. In this case, the current supplied to the pin 1 of the MJ 10 reaches the reverse connection confirmation circuit 12a through the other signal line 11 b. Thus, the light-emitting diode LD la lights up. Further, since the current passing through the light-emitting diode LDla reaches the pin 6 of the MJ 10, the light-emitting diode LDIb also lights up. Accordingly, in this case, it can be visually confirmed that the pins 1 and 2 of the MJ 10 are reversely connected.
Further, presence/absence of miswirlng between the different paired signal lines in the MJ 10 can also be visually confirmed using the LAN tester. For example, in Fig. 13(a), when the current is fed to 2 5 the pin 3 of the MJ 10, the light-emitting diodes LD 1 a and LD 1 b light up while the light-emitting diode LD2a, LD2b should light up in the ~2 p~ 7~9 -1 s-normal wiring. This represents that, as shown in the figure, the wiring in the MJ 10 is offset upward in turn, and thus, the miswiring can be visually confirmed. On the other hand, as shown in Fig. 13(b), if the light-emitting diodes LD2a and LD2b, which should not light up, light S up when the current is fed to the pin 1 of the MJ 10, it represents that the wiring of the MJ 10 is not normal. In this manner, the confirmation test of the connecting direction of the MJ 10 can be easily performed through combination of the timing of power feeding to the MJ 10 and the light-up pattern of the light-emitting diodes LD 1 a, LD 1 b, LD2a and LD2b.
Although the present invention has been explained showing the plurality of embodiments, the present invention is not limited to the foregoing embodiments. For example, although it is arranged that the energization state is detected using the light-emitting diode in the current detecting section 3 or the reverse connection confirmation circuit 12a, 12b, it may also be arranged that notification is made to the external through the meter display of flowing-current values or the sound (tone color or sound volume).
Industrial Applicability As described above, the LAN tester according to the present invention is capable of determining, based on presence/absence of the current detection by the current detecting section, whether there is a fault, such as disconnection, in the signal line, and confirming, based on presence / absence of the pulse detection by the forward polarity detecting section and the reverse polarity detecting section, whether the signal lines are in the normal polarity or the reverse polarity.
Further, a false signal can be produced by looping back pulses in the transmission signal lines to the reception signal lines so as to confirm the operation state of the hub or AUI to be connected.
Further, the misconnection of the wiring, etc. can also be easily confirmed.
_.~~.~__ _ ~T_.~..T_T.r __. _ ._ r~ _ _~.. __ ~_
S Disclosure of Invention For achieving the foregoing subject, when performing a conduction test, a LAN tester of the present invention selects (or non-optional) a conduction test mode as an operation mode by a change-over switch (first change-over switch), and comprises a power supply section for supplying, at one end of paired signal lines having two signal lines, a power supply current to one of the signal lines, and a current detecting section for detecting, at the one end of the paired signal lines to be tested, the current flowing in the signal line to which no power supply current is supplied by the power supply section. By this arrangement, when a fault, such as disconnection, exists in the signal line, the current is not detected by the current detecting section, while, when no abnormality exists in the signal line, a given current is detected by the current detecting section.
When performing a polarity test, a LAN tester of the present invention selects (or non-optional) a polarity test mode as an operation mode by a change-over switch (first change-over switch), and comprises a forward polarity detecting section for detecting positive pulses from a posifilve signal line and negative pulses from a negative signal line at one end of the signal lines to be tested, and a reverse polarity detecting section for detecting negative pulses from the positive signal line and positive pulses from the negative signal _~ __ . _ _ ~ ~ _ ~ . r.~.~_ ___ __ ._ line at the one end of the signal lines to be tested. By this arrangement, when the pulses are detected by the forward polarity detecting section, it is confirmed that the signal lines are in the normal polarity. On the other hand, when the pulses are detected by the reverse polarity detecting section, it is confirmed that the signal lines are in the reverse polarity.
When performing an operation test, a L.AN tester of the present invention selects (or non-optional) an operation test mode as an operation mode by a first change-over switch and a second change-over switch, and comprises a loopback connecting section for connecting terminals for connecting transmission signal lines and terminals for connecting reception signal lines, respectively.
a forward polarity detecting section for detecting positive pulses from a positive signal line and negative pulses from a negative signal line at one end of the signal lines to be tested, and a reverse polarity detecting section for detecting negative pulses from the positive signal line and positive pulses from the negative signal line at the one end of the signal lines to be tested. By this arrangement, since the pulses in the transmission signal lines are looped back to the reception signal lines so as to produce a false signal, an operation state of the hub or AUI (Attachment Unit Interface) (terminal) to be connected can be confirmed by the forward polarity detecting section and the reverse polarity detecting section.
When performing a confirmation test of a connecting direction, a LAN tester of the present invention, similar to the case of the conduction test, selects (or non-optional) a conduction test mode as an operation mode by a change-over switch (first change-over switch), t and comprises a power supply section for supplying a power supply current to one of signal lines at one end of the paired signal lines to be tested, a current detecting section for detecting, at the one end of the paired signal lines, the current flowing in the signal line to ~~hich no S power supply current is supplied by the power supply section, and a reverse connection confirmation circuit connected to the two signal lines at the other end of the paired signal lines. The reverse connection confirmation circuit includes a pair of unidirectional elements connected reversely in parallel, at least one of which unidirectional elements indicates a state thereof upon energization.
By this arrangement, since the states of the unidirectional elements in the reverse connection confirmation circuit differ depending on the forward connection and the reverse connection, the connection state can be confirmed.
For performing a confirmation test of connecting directions about a plurality of the paired signal lines, it is preferable to arrange a plurality of the reverse connection confirmation circuits, and provide power supply control means for controlling a power feed timing of the power supply section supplying a power supply current to the plurality of paired signal lines connected to the respective reverse connection confirmation circuits.
Brief Description of Drawings Fig. 1 is a circuit diagram showing an embodiment of a LAN
tester according to the present invention. Fig. 2 is a diagram showing a connection relationship to a hub or AUI when performing a conduction test using the LAN tester of the present invention. Fig. 3 is a diagram extracting the principal part of Fig. 1 for explaining an operation example in the conduction test using the LAN tester of the present invention. Fig. 4 is a diagram showing a connection relationship to a hub when performing a polarity test using the LAN
tester of the present invention. Fig. 5 is a diagram showing a connection relationship to a hub and an AUI when performing communication monitoring using the LAN tester of the present invention. Fig. 6 is a diagram extracting the principal part of Fig. 1 for explaining an operation example in the polarity test and the communication monitoring using the LAN tester of the present invention. Fig. 7 is a diagram showing a waveform example of trigger pulses (carrier component) in Fig. 4. Fig. 8 is a diagram showing a waveform example during communication in Fig. 5. Fig. 9 is a diagram showing a connection relationship to a hub or AUI when performing a simple operation test using the LAN tester of the present invention. Fig. 10 (a) and (b) are diagrams extracting the principal part of Fig. 1 for explaining an operation example in the simple operation test using the LAN tester of the present invention. Fig. 11 is a diagram showing a structural example wherein a confirmation test of presence/absence of miswiring of a universal 8-pin modular jack to be used in the LAN wiring is performed. Fig. 12(a) is a diagram showing a state wherein paired signal lines are connected in the forward direction. Fig. 12(b) is a diagram showing a state wherein the paired signal lines are reversely connected. Fig. 13 (a) and (b) are diagrams both showing states wherein misconnection exists between different paired signal lines.
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_,_ Best Mode for Carrying Out the Invention Now, an embodiment of a LAN tester of the present invention will be described with reference to Figs. 1-10.
Fig. 1 is a circuit diagram showing an example when carrying out the LAN tester. The LAN tester roughly includes a power supply section 2, a current detecting section 3, a forward polarity detecting section 4, a reverse polarity detecting section 5, a first change-over switch (change-over switch) 6, and a second change-over switch 7 having a function of a loopback connecting portion. In the figure, RA
and RB denote reception terminals, and SA and SB denote transmission terminals.
The power supply section 2 includes a power supply switch SWP
and an internal battery E. The current detecting section 3 includes a bipolar transistor ~3, light-emitting diodes LYl and LY2 which light up in yellow, and a plurality of resistors R 1, R7, R8 and R 14. The resistors R7 and R8 are provided for turning on the bipolar transistor ~3 while turning off a bipolar transistor (~2 so as to supply the power supply current to the transmission terminal SA. It is suitable to set R 1 and R 14 to about 56052, respectively, and R7 and R8 to about l OkS2.
The forward polarity detecting section 4 includes a bipolar transistor g4, a field-effect transistor ~5, a light-emitting diode LG
which lights up in green, resistors R12, R13, R15 and R16, and a capacitor C2. The reverse polarity detecting section 5 includes the bipolar transistor ~2, a field-effect transistor gl, a light-emitting diode LR which lights up in red, resistors R4, R5, R6 and R9, and a _ g_ capacitor C 1. The resistors R 10 and R 11 are provided for applying biases to the bipolar transistors ~2 and ~4. The capacitor C 1 and the resistor R5, and the capacitor C2 and the resistor R15 constitute smoothing circuits, respectively. It is suitable to set R6, R9, R 12 and S R 13 to about 1 kS2, respectively, R 10 to about 27052, R 11 to about 4.7kS2, R4 and R 16 to about 500kS2, respectively, R5 and R 15 to about 5MS2, respectively, and C 1 and C2 to about 0.1 ~,F, respectively.
As shown in Fig. 3, the first change-over switch 6 performs an on-off operation for a connection terminal 1 a and includes a switch SW 1 for connecting the transmission terminal SB to a connection terminal 2a or 2b. As shown in Fig. 10(b), the second change-over switch 7 includes a switch SW2 for connecting between the transmission terminal SA and the reception terminal RA and between the transmission terminal SB and the reception terminal RB.
Now, tests using the LAN tester of the present invention will be explained, respectively.
Fig. 2 is a diagram showing a connection relationship to a hub (or AUI) 20 when performing a conduction test using the LAN tester of the present invention. Fig. 3 is a circuit diagram extracting the principal part of Fig. 1 for explaining an operation example in the conduction test.
Specifically, in the conduction test, the bipolar transistor ~2 is turned off when the bipolar transistor ~3 is turned on, and monitoring of pilot data is stopped. Further, by opening the switch SW 1 (porrion 2b), a signal current does not flow to the bipolar transistor ~4 which thus does not operate. Accordingly, the LAN
_._ . __~~~~- . _.._ _~___ ._~ _ tester 1 shown in Fig. 1 becomes equivalent to a circuit shown in Fig.
3.
First, when performing a conduction test of reception lines, as shown in Fig. 2, the hub 20 is connected to the reception terminals S RA and RB of the LAN tester l, and the power supply switch SWP is closed. In this state, when the switch SW1 is pushed, the power supply current flows through the reception terminals RA and RB and then along a path of light-emitting diode LY1--thode D1-resistor Rl~switch SW1 (portion la)-ground GND as shown in Fig. 3, provided that the reception lines or the hub 20 is normal. Thus, the light-emitting diode LY1 lights up in yellow to notify to the external that the reception lines are normal.
On the other hand, if there is a fault, such as disconnection, in the reception line or the hub 20, the foregoing current path is interrupted. Thus, the light-emitting diode LY1 does not light up so that an occurrence of abnormality in the reception line or the hub 20 is recognized.
On the other hand, when performing a conduction test of transmission lines, as shown in Fig. 2, the hub 20 is connected to the transmission terminals SA and SB of the LAN tester 1, and the power supply switch SWP is closed. In this state, when the switch SW1 is pushed, the base current of the bipolar transistor ~3 flows to the ground GND through the resistor R8 and the switch SW1 (portion la) so that the bipolar transistor ~3 is turned on.
When the bipolar transistor ~3 is turned on, the power supply current flows through the transmission terminals SA and SB and -~~~..r. T.. r..~,."r,_~_~._ along a path of switch SW 1 (portion 2a)-resistor R 14-->light-emitting diode LY2-ground GND as shown in Fig. 3, provided that the transmission lines or the hub 20 is normal. Thus, the light-emitting diode LY2 lights up in yellow to notify to the external that the S transmission lines or the hub 20 is normal.
On the other hand, if there is a fault, such as disconnection, in the transmission line or the hub 20, the foregoing current path is interrupted. Thus, the light-emitting diode LY2 does not light up so that an occurrence of abnormality in the transmission line or the hub 20 is recognized.
As described above, the conduction test of the distribution cable is carried out through coils in the hub or AUI without using a loopback tool. Specifically, since no loopback tool is used, the conventional distribution cable tracing operation becomes unnecessary so that the labor for the searching operation can be largely reduced.
Fig. 4 is a diagram showing a connection relationship to a hub 40 when performing a polarity test using the LAN tester 1 of the present invention. Fig. 5 is a diagram showing a connection relationship to the hub 40 and an AUI 50 when performing communication monitoring using the LAN tester 1 of the present invention. Fig. 6 is a circuit diagram extracting the principal part of Fig. 1 for explaining an operation example in the polarity test and the communication monitoring.
Specifically, in the polarity test and the communication monitoring, since the bipolar transistor ~3 is turned off, the bipolar transistors ~2 and ~4 are activated. By connecting the switch SW1 ______...__ __~__.__.....
' 11-(portion 2b) to the terminal SB, the monitoring function of the pilot data is effected. Accordingly, the LAN tester 1 shown in Fig. 1 becomes equivalent to a circuit shown in Fig. 6.
As shown in Fig. 4, when performing a polarity test of the hub S 40, the hub is connected to the terminals SA and SB of the LAN
tester l, and the power supply switch SWP is closed. In this state, since the switch SW1 is not pushed, the base current does not flow to the bipolar transistor ~3. Thus, the bipolar transistor ~3 is turned off, and a certain bias is applied to the bipolar transistor ~2 and the bipolar transistor ~4 based on a voltage dividing ratio of the power supply voltage set by the resistors R 10 and R 11.
In this state, if a pulse signal as shown in Fig. 7 is applied as trigger pulses such that positive pulses are successively applied to the terminal SA and negative pulses are successively applied to the terminal SB, the base current intermittently flows to the bipolar transistor ~4 corresponding to the application of pulses. Thus, the bipolar transistor f~4 is intermittently turned on.
When the bipolar transistor ~4 is intermittently turned on, intermittent pulse voltages are applied to the field-effect transistor ~5 via the resistor R16. However, since the pulse voltages are smoothed by a time constant circuit constituted by the resistor R 15 and the capacitor C2, the field-effect transistor ~5 is turned on so that the light-emitting diode LG lights up in green to notify to the external that connection is performed with the correct polarity (forward polarity).
On the other hand, if negative pulses are successively applied to the terminal SA and positive pulses are successively applied to the T~,~_____ .~ J_~.. _r.~. _______ terminal SB, the base current intermittently flows to the bipolar transistor ~2 corresponding to the application of pulses. Thus, the bipolar transistor ~2 is intermittently turned on.
When the bipolar transistor ~2 intermittently is turned on, intermittent pulse voltages are applied to the field-effect transistor ~ 1 via the resistor R4. However, since the pulse voltages are smoothed by a time constant circuit constituted by the resistor R5 and the capacitor C 1, the field-effect transistor ~ 1 is turned on so that the light-emitting diode LR lights up in red to notify to the external that connection is performed with the wrong polarity (reverse polarity).
As described above, through the lighting-up of the light-emitting diode LG or the light-emitting diode LR, confirmation of presence/absence of the signal and confirmation of the polarity can be easily performed.
On the other hand, when performing the communication monitoring, the LAN tester 1 of the present invention is inserted between communication cables and, as shown in Fig. 5, the hub 40 and the AUI 50 are connected thereto. Accordingly, when a communication waveform as shown in Fig. 8 is applied, the communication state can be monitored through the foregoing operation in the polarity test.
Speci$cally, when a waveform is applied such that positive pulses are successively applied to the terminal SA and negative pulses are successively applied to the terminal SB, the light-emitting diode 2 S LG lights up in green. On the other hand, when a waveform is applied such that negative pulses are successively applied to the terminal SA
~~ i_i..~ _ __ _~.._~ J n---T-.-~-~ ___._ _ __ _ __.
and positive pulses are successively applied to the terminal SB, the light-emitting diode LR lights up in red. Accordingly, through the lighting-up of the light-emitting diode LG or LR, the signal can be easily monitored. As shown in Fig. 7, the signal voltages fed through S the cable for activating the transistor ~ 1 or ~5 are in the form of very short pulses. Thus, even if the light-emitting diode LG or LR is activated to light up based on these pulses, it is difficult to recognize it with the naked eye. In view of this, a width of a lighting time is ensured using the capacitor C 1 or C2 so as to make it easy to watch the lighting state.
As described above, the judgment of the polarity can be easily performed by detecting directions of the signal pulses, that is, based on the on-off states of the two light-emitting diodes LG and LR.
Fig. 9 is a diagram showing a connection relationship to the hub 40 when performing a simple operation test using the LAN tester 1 of the present invention. Fig. 10 is a diagram extracting the principal part of Fig. 1 for explaining an operation example in the simple operation test using the LAN tester of the present invention.
Specifically, in the simple operation test of the hub 40, since the bipolar transistor t~3 is turned off, the bipolar transistors ~2 and ~4 are activated. Further, since the pilot data monitoring function is activated by connecting the switch SW 1 (portion 2b) to the terminal SB, the LAN tester 1 shown in Fig. 1 becomes equivalent to a circuit shown in Fig. 10(a). As shown in Fig. 10(b), connections between the terminal RA and the terminal SA and between the terminal RB and the terminal SB are established for looping by closing the switch SW2.
T~ . _~_j.~
As shown in Fig. 9, when performing the simple operation test of the hub 40, the terminals SA and SB of the LAN tester are connected to the terminals RA and RB, respectively, and the power supply switch SWP is closed. Through this, pulses in the transmission lines are sent S to the reception lines so as to produce a false signal.
Specifically, as shown in Fig. 9, when the LAN tester 1 of the present invention is connected to the hub, the hub outputs again a signal voltage, as response data, into the transmission lines based on a looped-back signal. Accordingly, similar to the foregoing operation example in the communication monitoring, the simple operation test can be performed based on confirmation of PART/LINK of the hub 40 and irregular lighting-up/off of the light-emitting diodes LG and LR.
When the LAN tester 1 of the present invention is connected to the AUI, a simple operation test can be performed, similar to the case of the hub 40, based on lighting of R/L lamps of the AUI and irregular lighting-up/off of the light-emitting diodes LG and LR.
Specifically, the test of connection to the apparatus or the simple operation test can be accomplished simply by looping the signal lines.
As described above, by detecting the signal in the wiring to discriminate the presence / absence and the polarity thereof and performing the false operation test through the display using the light-emitting diodes and the looping by means of the LAN tester, the simple operation test of the hub or AUI and the confirmation of connection between the apparatuses can be achieved. Therefore, the disconnection, short circuit and polarity checks of a twisted-pair cable __._ . __._m.~~. ___T _.~~_ __ ,~~_ ..._ ._ of lOBASE-T as well as the simple connection test of the hub or AUI
can be achieved. Through this, if the LAN communication can not be achieved with the AUI, the test can be easily carried out to see whether the connections between the hub and the cable and between the cable and the AUI are securely performed. Thus, operation failure or contact failure of the hub, disconnection or short circuit of the cable, operation failure of the AUI or the like can be checked.
Further, in the conduction test, since the loopback tool, such as the loopback connector, is not used, it is not necessary to trace the distribution cable so that the searching operation is largely reduced, and further the test can be performed with one end of the cable connected to the apparatus. Thus, the confirmation of polarity and the operation test of the hub or AUI can be easily carried out.
In the foregoing embodiments, when performing the conduction test with the hub or AUI included, the hub or AUI is limited to such a type having a pulse transformer which forms a do loop in the HUB or AUI. On the other hand, no limiting conditions are given to the polarity test, the simple operation test, the communication monitoring and the like including the conduction test of the cable only.
Now, explanation will be given to a case wherein a confirmation test of a connecting direction of the wiring .is performed using the LAN
tester of the present invention. Fig. 11 is a diagram showing a structural example wherein, for example, a confirmation test of presence/absence of miswiring of a universal 8-pin modular jack to be used in the LAN wiring is performed. As shown in Fig. 11, the LAN
tester is provided with, for example, a plurality of reverse connection 2~ ~0 72~
confirmation circuits 12a, 12b ~ ~ ~ to be connected to corresponding reception terminals of the modular jack. Each of the reverse connection confirmation circuits 12a and 12b includes a diode D 11 (D 12) and a light-emitting diode LD 1a (LD2a) which are in reverse S connection.
One-side ends of paired signal lines 1 la and 1 lb are connected to pins 1 and 2 of a modular hack (MJ) 10 to be tested, respectively. To one of the paired signal lines, for example, to the signal line 11 a connected to the pin 1 of the MJ 10, is supplied the current from the forgoing power supply section 2 based on the do voltage Ea. further, between the signal line 11 b connected to the pin 2 of the MJ 10 and a grounding line is connected a light-emitting diode LD 1 b which lights up upon energization. The other-side ends of the signal lines 11 a and 11 b are connected to the foregoing reverse connection confirmation circuit 12a.
As shown in the figure, paired signal lines 11 c and 11 d are further connected to pins 3 and 6 of the MJ 10. Accordingly, similar to the case of the foregoing paired signal lines 11 a and 11 b, the current based on the do voltage Eb is supplied to the pin 3, a light-emitting diode LD2b is connected between the pin 6 and a grounding line, and a reverse connection confirmation circuit 12b is connected to the other-side ends of the paired signal lines 11 c and 11 d.
Upon performing the test, the currents based on the do voltages Ea and Eb are fed from the power supply section 2 at different timings, respectively. Since the known technique can be employed for switching itself of the power feed timing, it is not shown in the figure.
~~ p0 729 For the light-emitting diodes LD 1 b and LD2b, the circuits of the foregoing current detecting section 3 can be used as they are.
Now, a concrete example of the confirmation test of the connecting direction using the LAN tester with the foregoing structure will be described with reference to Figs. 12 and 13.
Fig. 12(a) is a diagram showing a state wherein the wiring of the MJ 10 is normal, that is, the paired signal lines 11 a and 11 b are connected in the forward direction. In this case, the current supplied through the pin 1 of the MJ 10 flows through the diode D 11 of the reverse connection confirmation circuit 12a to reach the pin 2 of the MJ 10 so that the light-emitting diode LDla lights up. Through this, it can be visually confirmed that the wiring of the MJ 10 is normal.
Fig. 12(b) is a diagram showing a state wherein the wiring of the MJ 10 is abnormal, that is, the paired signal lines 11 a and 11 b are reversely connected. In this case, the current supplied to the pin 1 of the MJ 10 reaches the reverse connection confirmation circuit 12a through the other signal line 11 b. Thus, the light-emitting diode LD la lights up. Further, since the current passing through the light-emitting diode LDla reaches the pin 6 of the MJ 10, the light-emitting diode LDIb also lights up. Accordingly, in this case, it can be visually confirmed that the pins 1 and 2 of the MJ 10 are reversely connected.
Further, presence/absence of miswirlng between the different paired signal lines in the MJ 10 can also be visually confirmed using the LAN tester. For example, in Fig. 13(a), when the current is fed to 2 5 the pin 3 of the MJ 10, the light-emitting diodes LD 1 a and LD 1 b light up while the light-emitting diode LD2a, LD2b should light up in the ~2 p~ 7~9 -1 s-normal wiring. This represents that, as shown in the figure, the wiring in the MJ 10 is offset upward in turn, and thus, the miswiring can be visually confirmed. On the other hand, as shown in Fig. 13(b), if the light-emitting diodes LD2a and LD2b, which should not light up, light S up when the current is fed to the pin 1 of the MJ 10, it represents that the wiring of the MJ 10 is not normal. In this manner, the confirmation test of the connecting direction of the MJ 10 can be easily performed through combination of the timing of power feeding to the MJ 10 and the light-up pattern of the light-emitting diodes LD 1 a, LD 1 b, LD2a and LD2b.
Although the present invention has been explained showing the plurality of embodiments, the present invention is not limited to the foregoing embodiments. For example, although it is arranged that the energization state is detected using the light-emitting diode in the current detecting section 3 or the reverse connection confirmation circuit 12a, 12b, it may also be arranged that notification is made to the external through the meter display of flowing-current values or the sound (tone color or sound volume).
Industrial Applicability As described above, the LAN tester according to the present invention is capable of determining, based on presence/absence of the current detection by the current detecting section, whether there is a fault, such as disconnection, in the signal line, and confirming, based on presence / absence of the pulse detection by the forward polarity detecting section and the reverse polarity detecting section, whether the signal lines are in the normal polarity or the reverse polarity.
Further, a false signal can be produced by looping back pulses in the transmission signal lines to the reception signal lines so as to confirm the operation state of the hub or AUI to be connected.
Further, the misconnection of the wiring, etc. can also be easily confirmed.
_.~~.~__ _ ~T_.~..T_T.r __. _ ._ r~ _ _~.. __ ~_
Claims (7)
1. In a LAN including a line: concentrator provided therein with a circuit for forming a do loop, a method of performing a conduction test comprising the steps of:
connecting a LAN tester to a pair of signal lines while said pair of signal lines are connected to said line concentrator;
supplying a current to one of said pair of signal lines from the LAN
tester; and detecting by the LAN tester said current flowing in the other of said pair of signal lines, said current returning from said line concentrator in the do loop formed by said circuit provided in the line concentrator.
connecting a LAN tester to a pair of signal lines while said pair of signal lines are connected to said line concentrator;
supplying a current to one of said pair of signal lines from the LAN
tester; and detecting by the LAN tester said current flowing in the other of said pair of signal lines, said current returning from said line concentrator in the do loop formed by said circuit provided in the line concentrator.
2. The method according to claim 1, wherein said line concentrator is one of a hub and an AUI.
3. In a LAN including a line concentrator, a method of performing a polarity test of a signal sent from the line concentrator comprising the steps of:
connecting a first and a second terminal of a LAN tester to a pair of signal lines, respectively, while said pair of signal lines are connected to said line concentrator;
receiving at said first terminal of the LAN tester positive pulses from said line concentrator via one of said pair of signal lines and at said second terminal of the LAN tester negative pulses from said line concentrator via the other of said pair of signal lines; and detecting at a forward polarity detecting section of said LAN tester the positive pulses received at said first terminal and the negative pulses received at said second terminal when said first terminal is for receiving the positive pulses and said second terminal is for receiving the negative pulses, while detecting at a reverse polarity detecting section of said LAN tester the positive pulses received at said first germinal and the negative pulses received at said second terminal when said first terminal is for receiving the negative pulses and said second terminal is for receiving the positive pulses, whereby judging whether the signal sent from said line concentrator has a forward or reverse polarity.
connecting a first and a second terminal of a LAN tester to a pair of signal lines, respectively, while said pair of signal lines are connected to said line concentrator;
receiving at said first terminal of the LAN tester positive pulses from said line concentrator via one of said pair of signal lines and at said second terminal of the LAN tester negative pulses from said line concentrator via the other of said pair of signal lines; and detecting at a forward polarity detecting section of said LAN tester the positive pulses received at said first terminal and the negative pulses received at said second terminal when said first terminal is for receiving the positive pulses and said second terminal is for receiving the negative pulses, while detecting at a reverse polarity detecting section of said LAN tester the positive pulses received at said first germinal and the negative pulses received at said second terminal when said first terminal is for receiving the negative pulses and said second terminal is for receiving the positive pulses, whereby judging whether the signal sent from said line concentrator has a forward or reverse polarity.
4. The method according to claim 3, further comprising the steps of:
connecting said first and second terminals of the LAN tester to a third and fourth terminal of the LAN tester, and connecting said third and fourth terminals to said line concentrator via another pair of signal lines, thereby to return the positive and negative pulses received at said first and second terminals to said line concentrator as a false signal via said third and fourth terminals; and receiving at said first and second terminals of the LAN tester positive and negative pulses from said line concentrator as a response signal responsive to said false signal, whereby an operation test of said line concentrator is performed.
connecting said first and second terminals of the LAN tester to a third and fourth terminal of the LAN tester, and connecting said third and fourth terminals to said line concentrator via another pair of signal lines, thereby to return the positive and negative pulses received at said first and second terminals to said line concentrator as a false signal via said third and fourth terminals; and receiving at said first and second terminals of the LAN tester positive and negative pulses from said line concentrator as a response signal responsive to said false signal, whereby an operation test of said line concentrator is performed.
5. The method according to claim 3, wherein said line concentrator is one of a hub and an AUI.
6. A LAN tester connected to a line concentrator of a LAN, said LAN tester comprising:
a first and a second terminal for receiving positive pulses and negative pulses, respectively, from said line concentrator via a first pair of signal lines;
a forward polarity detecting section for detecting the positive pulses and the negative pulses received from said line concentrator when said first terminal actually receives the positive pulses and said second terminal actually receives the negative pulses;
a reverse polarity detecting section for detecting the positive pulses and the negative pulses received from said line concentrator when said first terminal actually receives the negative pulses and said second terminal actually receives the positive pulses; and a loopback connector for connecting said first and second terminals to a third and a fourth terminal, respectively, thereby to return the received positive and negative pulses to said line concentrator as a false signal via a second pair of signal lines connecting said third and fourth terminals to said line concentrator.
a first and a second terminal for receiving positive pulses and negative pulses, respectively, from said line concentrator via a first pair of signal lines;
a forward polarity detecting section for detecting the positive pulses and the negative pulses received from said line concentrator when said first terminal actually receives the positive pulses and said second terminal actually receives the negative pulses;
a reverse polarity detecting section for detecting the positive pulses and the negative pulses received from said line concentrator when said first terminal actually receives the negative pulses and said second terminal actually receives the positive pulses; and a loopback connector for connecting said first and second terminals to a third and a fourth terminal, respectively, thereby to return the received positive and negative pulses to said line concentrator as a false signal via a second pair of signal lines connecting said third and fourth terminals to said line concentrator.
7. The LAN tester according to claim 6, wherein said line concentrator is one of hub and an AUI.
Applications Claiming Priority (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7-189992 | 1995-07-26 | ||
| JP18999295 | 1995-07-26 | ||
| JP8-132164 | 1996-05-27 | ||
| JP13216496A JP3264827B2 (en) | 1995-07-26 | 1996-05-27 | LAN tester |
| PCT/JP1996/002106 WO1997005494A1 (en) | 1995-07-26 | 1996-07-26 | Lan tester |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2200729A1 CA2200729A1 (en) | 1997-02-13 |
| CA2200729C true CA2200729C (en) | 2001-10-16 |
Family
ID=26466795
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002200729A Expired - Fee Related CA2200729C (en) | 1995-07-26 | 1996-07-26 | Lan tester |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US6087835A (en) |
| EP (1) | EP0784207A4 (en) |
| JP (1) | JP3264827B2 (en) |
| KR (1) | KR100258708B1 (en) |
| AU (1) | AU703954B2 (en) |
| CA (1) | CA2200729C (en) |
| WO (1) | WO1997005494A1 (en) |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6480510B1 (en) | 1998-07-28 | 2002-11-12 | Serconet Ltd. | Local area network of serial intelligent cells |
| US6434716B1 (en) * | 1999-01-29 | 2002-08-13 | Psiber Data Systems Inc. | Network link tester device configured to selectively and automatically couple to a network transmit pair line or a node transmit pair line of a LAN port and determine available operational modes |
| US6956826B1 (en) | 1999-07-07 | 2005-10-18 | Serconet Ltd. | Local area network for distributing data communication, sensing and control signals |
| US6549616B1 (en) | 2000-03-20 | 2003-04-15 | Serconet Ltd. | Telephone outlet for implementing a local area network over telephone lines and a local area network using such outlets |
| US6842459B1 (en) | 2000-04-19 | 2005-01-11 | Serconet Ltd. | Network combining wired and non-wired segments |
| US6961303B1 (en) | 2000-09-21 | 2005-11-01 | Serconet Ltd. | Telephone communication system and method over local area network wiring |
| US6459275B1 (en) * | 2001-02-28 | 2002-10-01 | Avaya Technology Corp. | Detection of devices on a local area network |
| JP2002261787A (en) * | 2001-03-05 | 2002-09-13 | Allied Tereshisu Kk | Signal confirmation deciding equipment for lan, signal confirmation deciding method for lan and signal confirmation deciding program for lan |
| US6483318B1 (en) * | 2001-06-29 | 2002-11-19 | Ideal Industries, Inc. | Electric circuit providing selectable short circuit for instrumentation applications |
| JP5167568B2 (en) * | 2001-09-28 | 2013-03-21 | テンパール工業株式会社 | Branch circuit connection check device for distribution board |
| IL152824A (en) | 2002-11-13 | 2012-05-31 | Mosaid Technologies Inc | Addressable outlet and a network using same |
| DE10343723B4 (en) * | 2003-09-22 | 2007-09-27 | Ria-Btr Produktions-Gmbh | Apparatus for testing the installation of the junction boxes of an ISDN So bus system |
| IL159838A0 (en) | 2004-01-13 | 2004-06-20 | Yehuda Binder | Information device |
| US7936671B1 (en) * | 2007-11-12 | 2011-05-03 | Marvell International Ltd. | Cable far end port identification using repeating link state patterns |
| JP5704690B2 (en) * | 2010-11-16 | 2015-04-22 | 九電テクノシステムズ株式会社 | Abnormality detection device for composite cable of wired paging system |
| US8447845B1 (en) | 2011-02-10 | 2013-05-21 | Flir Systems, Inc. | Setting a network device to default settings |
| JP5505887B2 (en) * | 2011-09-12 | 2014-05-28 | テンパール工業株式会社 | Branch circuit connection check device for distribution board |
| JP6193575B2 (en) * | 2013-01-29 | 2017-09-06 | 京セラ株式会社 | Energy management apparatus, energy management system, and energy management method |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5943373A (en) * | 1982-09-06 | 1984-03-10 | Fujitsu Ltd | Continuity tester |
| US4551671A (en) * | 1983-06-23 | 1985-11-05 | International Business Machines Corp. | Terminal disconnect and media wire fault detect mechanism |
| JPS646878A (en) * | 1987-06-30 | 1989-01-11 | Yaskawa Denki Seisakusho Kk | Differential digital transmission line |
| CA1315858C (en) * | 1987-10-30 | 1993-04-06 | David Douglas Clegg | Telecommunications wiring test apparatus and method |
| JPH0330874U (en) * | 1989-08-02 | 1991-03-26 | ||
| FR2653893B1 (en) * | 1989-10-26 | 1992-05-22 | Fieau Jean Claude | DEVICE FOR TESTING A BUS WITH TWO PAIRS OF CONDUCTORS. |
| US5257287A (en) * | 1990-02-15 | 1993-10-26 | Advanced Micro Devices, Inc. | Automatic polarity detection and correction method and apparatus employing linkpulses |
| JPH04269668A (en) * | 1991-02-25 | 1992-09-25 | Matsushita Electric Works Ltd | Inspecting device for twisted pair line |
| US5228072A (en) * | 1991-05-29 | 1993-07-13 | Independent Technologies, Inc. | Multiwire-pair telecommunications test system |
| USH1369H (en) * | 1991-07-29 | 1994-11-01 | Verbin; Randolph N. | Cable continuity test apparatus |
| US5315597A (en) * | 1992-05-08 | 1994-05-24 | Digital Equipment Corporation | Method and means for automatically detecting and correcting a polarlity error in twisted-pair media |
| US5598342A (en) * | 1995-01-31 | 1997-01-28 | The Siemon Company | Cable tester |
-
1996
- 1996-05-27 JP JP13216496A patent/JP3264827B2/en not_active Expired - Lifetime
- 1996-07-26 US US08/809,808 patent/US6087835A/en not_active Expired - Fee Related
- 1996-07-26 WO PCT/JP1996/002106 patent/WO1997005494A1/en not_active Application Discontinuation
- 1996-07-26 CA CA002200729A patent/CA2200729C/en not_active Expired - Fee Related
- 1996-07-26 KR KR1019970701568A patent/KR100258708B1/en not_active IP Right Cessation
- 1996-07-26 AU AU65315/96A patent/AU703954B2/en not_active Ceased
- 1996-07-26 EP EP96925099A patent/EP0784207A4/en not_active Ceased
Also Published As
| Publication number | Publication date |
|---|---|
| WO1997005494A1 (en) | 1997-02-13 |
| KR970705756A (en) | 1997-10-09 |
| AU703954B2 (en) | 1999-04-01 |
| JPH0996656A (en) | 1997-04-08 |
| EP0784207A4 (en) | 2001-08-22 |
| KR100258708B1 (en) | 2000-06-15 |
| JP3264827B2 (en) | 2002-03-11 |
| CA2200729A1 (en) | 1997-02-13 |
| US6087835A (en) | 2000-07-11 |
| AU6531596A (en) | 1997-02-26 |
| EP0784207A1 (en) | 1997-07-16 |
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Legal Events
| Date | Code | Title | Description |
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| EEER | Examination request | ||
| MKLA | Lapsed |